effects of dietary aloe vera and echinacea on some nonspecific immunity in shirbot (barbus grypus)

A feeding trial was conducted for sixty continuous days to determine the effect of dietary aloe vera and echinacea on immunological parameters of shirbot (barbus grypus). four hundred and twenty fish weighing 50-60 g were randomly subjected to seven different treatment, including one control (aloe vera and echinacea free diet), a1 (0.1% of aloe vera), a2 (0.2% of aloe vera), a3 (0.5% of aloe vera), e1 (0.1% of echinacea), e2 (0.2% of echinacea), e3 (0.5% of echinacea) each in triplicate. some immunological parameters such as respiratory burst activity, complement activity, lysozyme activity, serum bactericidal activity, total protein and albumin were assessed. at the end of treatment, 30 fish from each group were challenged with aeromonas hydrophila. no significant difference was seen in respiratory burst activity of aloe vera and echinacea treatments compared to the control group (p>0.05).complement and serum bactericidal activity enhanced in all the aloe vera groups (p<0.05). total protein and globulin in aloe vera and echinacea treatments decreased compared with control group (p>0.05). lysozyme activity in 0.2% aloe vera treatments was significantly higher than echinace and control groups (p<0.05). according to obtained results, it might be concluded that the feeding of this species by aloe vera (specifically 0.2%) extract could likely enhance immunological parameters better than echinacea.